Making a new bass cover plate...

[Rosie C]

I've been umm-ing and aah-ing over microphones for my accordion for weeks now. Let me run this idea past you

Within our Morris band a mandolin plays the melody, my most important contribution is the harmony chords and bass line (I even wrote an essay for for my uni. course on this!) But while I can amplify the treble side using a vocal mic on a mic stand, I can't do that with the bass as it moves with the bellows.

I can't afford the £890 my local pro wants for a quality mic installation - and I am averse to drilling holes for volume and jack sockets anyway. But I had an idea last night - if I buy some aluminium plate I could make a new bass cover and fit a bass microphone and XLR socket to it - all completely reversible by replacing the original bass cover. I could add treble mics later if I need - feeding the wires through the bellows in the reverse direction to most mic systems. But for now I'll just do bass I think. I already have some T.bone miniature mics to experiment with. I can use a cable for now, but later I can splurge on a pair of Xvive wireless XLR dongles with built-in phantom power.

 

[Dingo40]

But I had an idea last night - if I buy some aluminium plate I could make a new bass cover and fit a bass microphone and XLR socket to it - all completely reversible by replacing the original bass cover.

That brain of yours never stops working!
Sounds good!

 

[debra]

This situation is exactly where the Microvox system comes in handy. A mic bar (4 capsules) for the treble side, attached to the outside of the grille with velcro plus one mic capsule for the bass side, also attached with velcro, and positioned over one of the holes in the bass plate, and a separate power supply with volume control. I have used this for many years. You don't put it on when you are playing at home and just attach (and remove afterwards) for playing with the band. So it's three separate parts: M410 or M420 for the treble side (depending on the size of the accordion), M400 single mic for the bass and then the power supply with volume control. Comes in way less expensive than what the local pro wants, and it requires no installation.

 

[Rosie C]

This situation is exactly where the Microvox system comes in handy. A mic bar (4 capsules) for the treble side, attached to the outside of the grille with velcro plus one mic capsule for the bass side, also attached with velcro, and positioned over one of the holes in the bass plate, and a separate power supply with volume control.

I did look at this, and it seems ideal. Especially anything that avoids drilling holes in my accordion.

But I thought that Microvox had stopped trading?

 

[debra]

Accordion/Melodeon microphones by Microvox

Microvox used to have their own website where you could order direct,
but it seems that mrmicrophone.com has taken over that function.
There are other sites (in other countries including mine) that also sell Microvox mics, so I have hopes that they are still in business because they have an awesome product series.

 

[jozz]

I did look at this, and it seems ideal. Especially anything that avoids drilling holes in my accordion.

But I thought that Microvox had stopped trading?

Carini sells a similar external mic, either MusicTech MT-05 or Master

https://carinidena.it/MS5ECOMMERCE60/files/articoli/35789-01.jpg

 

[Rosie C]

Accordion/Melodeon microphones by Microvox

Microvox used to have their own website where you could order direct,
but it seems that mrmicrophone.com has taken over that function.
There are other sites (in other countries including mine) that also sell Microvox mics, so I have hopes that they are still in business because they have an awesome product series.

The phone number on the mrmicrophone website doesn't work. I've sent an email to the address given, but it's in the "demon.co.uk" domain which is what everyone in the UK used in the 1990s and is defunct. But, let's see if it produces anything!

I have found a dealer in Canada that seems to have one in stock - I've emailed to check.

 

[Rosie C]

Carini sells a similar external mic, either MusicTech MT-05 or Master

https://carinidena.it/MS5ECOMMERCE60/files/articoli/35789-01.jpg

Thanks! I've looked at these before and it was going to cost in excess of £400

 

[debra]

Thanks! I've looked at these before and it was going to cost in excess of £400

That's less than half of what the professional quoted...

 

[Rosie C]

That's less than half of what the professional quoted...

That is true. But it's still quite a lot - if I was paying that much I would prefer an internal system - mostly we perform outdoors and I'd feel happier with everything inside. Also, although I'm new to accordion I've been an amateur musician for years and I have accumulated all manner of cables, mics, amplifiers - it seems I should be able to cobble something together.

 

[Ventura]

an aluminum replacement plate will be very cold outdoors and unpleasant

i tried mic's mounted on the bass cover plate once and there is just
a huge amount of vibration to overcome there, even with thick foam
mounting the mic capsules picked up way too much noise
(including every tume your hand moves/slides it creates noise
that can be picked up)

XLR is huge and unwieldy i feel by comparison, components are also quite heavy
for the wireless you are looking at, plus it has no ability to swap a battery out

sorry, i dislike this approach a lot

please look at the end-tail acoustic guitar through body jacks.. they can be
had in a long bodied threaded form and are easy to install. There is ample room
below the bass notes and it is minimally invasive. Personally i usually
also add a volume control next to the jack, but if you use a wireless that
has a volume control on it, that is fine.

in practical use, having to run back to the Amp or PA system everytime
there is a sudden audio problem is a "gotcha" to be avoided

You could cut a new bassplate out of LEXAN/Persepex and install a normal 1/4"
jack in a lower corner where your hand wouldn't ever bother, and mount the Mic
in the chamber, but then you will need a small slip-connector and slack in the
connecting cable

 

[Rosie C]

A most useful reply @Ventura , thanks! I like the lexan idea a lot - not least because I have already have a sheet of 5mm that I could use.

I've attached a photo of the microphones I have. I'm not sure of the brand but they're identical to the T.bone system that Thomann sells. The mic has a metre or so of thin cable terminating in a 3.5mm stereo jack, then there is a jack->XLR adaptor. I'm not sure whether this just changes the plug or whether it's doing something electrically too. The mics need phantom power which has been a sticking point as I'm using a guitar amp which doesn't support that. I can put a little mixing desk in-line, but for example - we're dancing in January stopping 15 minutes each at five pubs through the afternoon. The idea of my accordion with a wireless dongle sticking out of the side, and my battery guitar amp with a dongle on its input seems ideal - no wires, no other equipment to carry.

I've attached a sketch too, showing how I thought I might mount the bass mic. Our Morris tunes are only ever in G or D. I expect if I'm still playing Morris in 10 years time then the C, G, D and A buttons will be worn out while the Db, Ab, Eb buttons will be pristine, so I'm not too worried if the output jack stops me getting to the bottom end of the stradella board. I've not drawn the XLR on because I'm looking at the 3.5mm jack on the mic and wondering if that's a better option - and keep the jack-XLR adapter outside.

 

[Ventura]

working with Lexan, remember it is somewhat brittle

cutting with a very fine jig-saw or hand held blade slowly and
patiently

drilling holes very gently

the 4 corner screws to mount it to the accordion, i used spare
rubber washers from my replacement faucet washer assortment
to hold the pressure but not directly put the metal screw on the lexan

(i put my Dallape Stradella section under "glass" once as a show and tell)

 

[Ventura]

the phantom power for Electret mic's is a simple circuit,
48 volts is not necessary, the few volts from the transmitter
pack is sufficient OR simply wire a battery into your circuit

you have 3 possible connections to the mic element
ground (usually black)
power (typically red)
signal (white or clear)

Power will feed through a resistance, but will be blocked by a capacitance,
signal will pass through a capacitance, but prefer not to flow through a resistance
(the path of least resistance) and this is how you control it

so ground is common to the battery and Mic and Transmitter
the positive leg of the mic (the shielded wire) goes to a
1 Microfarad 16 Volt capacitor AND to a 1000 Ohm small resistor
the other leg of the Capacitor goes to the transmitter/mixer input
the other leg of the resistor goes to the + voltage (wherever it comes from)
and it works

the gooesneck mic in your photo has a 3 way plug. That may mean the + voltage
is connected to the middle band with ground being the base and signal being tip
if you want to test a circuit on the workbench using it

 

[jozz]

I'm not sure whether this just changes the plug or whether it's doing something electrically too.

Seeing the mic is quite large, my bet is it houses its own pre-amp circuit, and the plug is just a adapter, like the Thomann 'Lucan' system.

It doesn't matter if the pre-amp is at the capsule or the adapter, connected to the U3c you will always carry a somewhat long 'stick' on your belt
- we use a similar setup, but then for wireless headsets.

Something to consider with small instruments like flutes (or headsets) - for those situations you're better off with the tiniest mic that has the pre-amp in the adapter. The adapter on the hip will then be slightly heavier.

As a sound engineer, I carry both the U3c, an active Lucan gooseneck with clamps, and several passive headset and lavalier mics for the oddball instrument that can take it. This kit can solve lots of situations where some form of lightweight wireless on the go solution is needed.

maybe for Morris a tiny lavalier on the bass-strap, with pre-amp + U3c adapter on the hip would be suited
this saves you from fabricating a new plate, and can carry over to other instruments

 

[dak]

One of the smallest(?) 2-pin LEMO connectors (I'd need to look up its exact name) has historically been used for 3-wire electret microphone installations in accordions. The socket will fit a typical bass plate slot almost exactly.

I actually have most of the parts for a bass-side microphone installation here. I had picked MEMS microphones to work with and use a FET for voltage regulation and signal buffering. That way, a typical wireless transmitter or other electret microphone adapter should be able to feed 5 microphones or so on a 2-wire circuit. The microphones are tiny; the wiring and mounting makes for the most puzzling task.

At any rate, I think the LEMO connectors are a good fit. Certainly provide for a more reliable and robust connection than 3.5mm TRS. A full-size XLR does not make a whole lot of sense in an accordion to me. Mini-XLR (also known as TQG) is more reasonable, but the sockets are less compact than the LEMO solution.

 

[Rosie C]

Thanks for all the replies, I have spent hours over the last few weeks working through the various options. I wasn't really happy with any of the options, so have plumbed with buying another accordion that comes with pre-installed mics. More on that on another thread!